Gatty Marine Laboratory, St. Andrews. 129 
bristles of the first thoracic segment. He was fully aware 
of its approach to the Serpulids and Filograna, yet the 
absence of an operculum separates it from both, though 
there can be no question of its close affinity with Filogr and, 
the more so as Salmacina reproduces by posterior buds. 
He thought that Protula dysteri, which De Quatrefages 
united with Féilograna, should probably be embraced in his 
genus, though the enlargements at the tips of the branchial 
filaments do not merit the name of opercula. He mentions, 
further, that it would be as reasonable to include the eyes 
at the tips of the branchiz in Branchiomma as opercular as 
such swellings in Protula dysteri. 
His first species was S. incrustans *, which he thought might 
be synonymous with Serpula incrustans (Linn.), “Grube le 
and Serpula filograna of Sacchit. Inhis specific characters, 
however, no distinctive feature of moment is recognizable, 
for in length (2 to 2°5 mm.), colour, the number of the 
thoracic segments (8), the three kinds of dorsal bristles, the 
pectinate uncini, the flexuous calcareous tube incrusting 
Zostera and other marine organisms, aud the hermaphrodite 
condition, there is nothing diagnostic. Thus Langerhans 
subsequently showed that even the number of the thoracic 
segments varied in this form from seven to nine. The 
presence of eyes again corresponds with the condition in 
Vilograna implexa and Salmacina dysteri, as also does the 
structure of the first pair of thoracic bristles ; though the 
bolder character of their serrations above the ‘* knee” indi- 
cates variation, it may be from environment, whilst the absence 
of serrations in the tapering blade beyond the hiatus in 
Claparéde’s description and figure is due to the artist, for 
they are present in specimens from Naples. ‘The description 
and figures of the two other forms of bristles agree with the 
conditions in Filograna; and the same may be said of the 
abdominal bristles and the structure of the hooks. Claparede 
found in one a double tip to the tail with two cirri, perhaps 
the result of injury. 
He regarded the anterior glands (nephridia) as the 
secretory organs for the tubes. Further, he describes the 
hermaphrodite animal as provided with orange ova in the 
anterior region of the abdomen, and zoosperms in the poste- 
rior, even to the extremity, and ‘the sperms had an elongated 
head. Such an arrangement therefore differs from Thee 
usually observed. 
* Op. cit. p. 486. 
+ Echeniod Actin, u. Wiirmer, p. 62. 
{ Catal. Conch. reg. Neapol. p. 19, 1836 (side Claparéde), 
Ann. & Mag. N. Hist. Ser. 9. Vol. lil. ) 
